When to use metadata.clone(), metadata.clone_dirty(), Metadata::new()

[niklasdewally]

• Under what circumstances should I use metadata.clone_dirty() vs metadata.clone() when writing rules?

• If I am rewriting an expression and its children to some new expression excluding some of those children, what should happen to the metadata? Are there any general guidelines?

• My current assumption is that some of this is implicitly managed by the rule_engine: where does the buck stop?

@YehorBoiar @lixitrixi @ozgurakgun

[ozgurakgun]

I think creating a dirty metadata is the safe thing to do.

[niklasdewally]

I think creating a dirty metadata is the safe thing to do.

I think the rewriter makes things dirty itself for me, so clone_dirty() and clone() work the same functionally.